MARSHFIELD, Wis. (May 9)—Cast urethane product maker and molder PCO Inc. has been purchased by Mike Johnson, owner of Morton, Minn.-based Flexor Inc., for an undisclosed amount. Johnson, who has assumed the firm's presidency, is setting up a program to expand the 20-year-old company's sales foundation. He plans to eventually merge his two businesses, blend each operation's product lines and enlarge his sales force during the next fiscal year. Johnson bought PCO from John and Rosemary Christenson, who are retiring, he said. The new owner said he pursued the acquisition because of PCO's strong reputation and good product mix.